After a Taurus XL launch vehicle failed to loft the Orbiting Carbon Observatory (OCO) in February 2009, NASA used another Taurus XL to launch the Glory climate-monitoring spacecraft despite a recommendation from its own engineering safety office to ground the Orbital Sciences Corp. rocket until key components could be requalified.
The agency accepted the risk of a similar mishap on the March 2011 Glory launch attempt that was calculated as high as 50%, a gamble that resulted in the loss of the $424-million mission when the vehicle's payload shroud once again failed to open and pulled the satellite into the ocean off Antarctica.
Since then, NASA has decided against using a Taurus XL to launch the replacement OCO-2 mission. Other Orbital vehicles, including the air-launched Pegasus and a new Antares rocket, use a version of the same fairing separation system that is most likely responsible for the combined $700 million loss of two key climate-study satellites. Orbital's original name for Antares was Taurus II.
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